It's great that introductions will be done in a neutral place. However moving is very stressful for cats, so I would not do the introductions immediately upon moving.
Here is what I recommend.
Start exchanging scents now. Get a couple of t-shirts you and your boyfriend have worn. Rub your shirt all over your cats, and bring that shirt to his cats let them smell it, and them rub it on them. At the same time do this with his cats also, rub his shirt on his cats, then let your cats smell it, and then rub it on them.
Bring each shirt back and forth as often as possible before the move so they become more familiar with the scents of one another, and smell the strange scents blended with theirs.
When moving, it is always best to keep the cats contained to one room in the new place at first, and after a few days gradually allow them access to the rest of the house.
Does the new house have enough rooms to do this for each set of cats?
Install feliway diffusers in the new house.
Continue the scent exchanges with each set of cats in their own rooms in the new house.
When you begin letting them out of their rooms to explore more, allow one set at a time. For instance let your cats roam around, then put them back in your room, and let his cats roam.
It won't take each set long to find the door behind which the other cats are staying, so they will quickly become aware of each other.
Once all cats have been all through the house, except the other cats' room, switch rooms and do the release and roam again, but each set of cats will be in the other cats' room, learning the smells of the other cats.
After a few more days of this, let them out and see how they do.
Make sure to have plenty of perching spaces for EVERYONE, before letting them all meet.
Make sure you have enough litter boxes, five, ideally.
If possible I would put screen doors in the doorways of the two rooms, so they can meet face to face safely.
I have a screen door in my bedroom door way for this purpose (for when I bring in a new cat)
congratulations on your new home, and welcome to Paw Talk. Let us know how things go!